A Novel Strategy for Plant Virus Resistance Using Artificial miRNA

Abstract

Plant micro-RNAs (miRNAs) are 21-nt-long Small RNAs that regulate the abundance of target mRNAs by guiding cleavage at the sequence complementary region. We found that DNA sequences encoding Aiabidopsis pre-miRNAs can be expressed from a 35S promoter in transgenic plants to produce mature miRNAs. Moreover, sequences in pre-miRNAs can be modified to produce artificial miRNAs (amiRNAs) of a pre-determined sequence. Here, we describe a novel strategy to express amiRNA designed to target and degrade offending viral RNAs thereby conferring specific resistance. The amiRNA-mediated approach should have broad applicability for engineering multiple virus resistance in crop plants.